/* SPDX-License-Identifier: GPL-2.0-only */

  /*
   * FSI master definitions. These comprise the core <--> master interface,
   * to allow the core to interact with the (hardware-specific) masters.
   *
   * Copyright (C) IBM Corporation 2016

   */
  
  #ifndef DRIVERS_FSI_MASTER_H
  #define DRIVERS_FSI_MASTER_H
  
  #include <linux/device.h>

  #include <linux/mutex.h>

  /*
   * Master registers
   *
   * These are used by hardware masters, such as the one in the FSP2, AST2600 and
   * the hub master in POWER processors.
   */
  
  /* Control Registers */
  #define FSI_MMODE		0x0		/* R/W: mode */
  #define FSI_MDLYR		0x4		/* R/W: delay */
  #define FSI_MCRSP		0x8		/* R/W: clock rate */
  #define FSI_MENP0		0x10		/* R/W: enable */
  #define FSI_MLEVP0		0x18		/* R: plug detect */
  #define FSI_MSENP0		0x18		/* S: Set enable */
  #define FSI_MCENP0		0x20		/* C: Clear enable */
  #define FSI_MAEB		0x70		/* R: Error address */
  #define FSI_MVER		0x74		/* R: master version/type */
  #define FSI_MSTAP0		0xd0		/* R: Port status */
  #define FSI_MRESP0		0xd0		/* W: Port reset */
  #define FSI_MESRB0		0x1d0		/* R: Master error status */
  #define FSI_MRESB0		0x1d0		/* W: Reset bridge */
  #define FSI_MSCSB0		0x1d4		/* R: Master sub command stack */
  #define FSI_MATRB0		0x1d8		/* R: Master address trace */
  #define FSI_MDTRB0		0x1dc		/* R: Master data trace */
  #define FSI_MECTRL		0x2e0		/* W: Error control */
  
  /* MMODE: Mode control */
  #define FSI_MMODE_EIP		0x80000000	/* Enable interrupt polling */
  #define FSI_MMODE_ECRC		0x40000000	/* Enable error recovery */
  #define FSI_MMODE_RELA		0x20000000	/* Enable relative address commands */
  #define FSI_MMODE_EPC		0x10000000	/* Enable parity checking */
  #define FSI_MMODE_P8_TO_LSB	0x00000010	/* Timeout value LSB */
  						/*   MSB=1, LSB=0 is 0.8 ms */
  						/*   MSB=0, LSB=1 is 0.9 ms */
  #define FSI_MMODE_CRS0SHFT	18		/* Clk rate selection 0 shift */
  #define FSI_MMODE_CRS0MASK	0x3ff		/* Clk rate selection 0 mask */
  #define FSI_MMODE_CRS1SHFT	8		/* Clk rate selection 1 shift */
  #define FSI_MMODE_CRS1MASK	0x3ff		/* Clk rate selection 1 mask */
  
  /* MRESB: Reset brindge */
  #define FSI_MRESB_RST_GEN	0x80000000	/* General reset */
  #define FSI_MRESB_RST_ERR	0x40000000	/* Error Reset */
  
  /* MRESP: Reset port */
  #define FSI_MRESP_RST_ALL_MASTER 0x20000000	/* Reset all FSI masters */
  #define FSI_MRESP_RST_ALL_LINK	0x10000000	/* Reset all FSI port contr. */
  #define FSI_MRESP_RST_MCR	0x08000000	/* Reset FSI master reg. */
  #define FSI_MRESP_RST_PYE	0x04000000	/* Reset FSI parity error */
  #define FSI_MRESP_RST_ALL	0xfc000000	/* Reset any error */
  
  /* MECTRL: Error control */
  #define FSI_MECTRL_EOAE		0x8000		/* Enable machine check when */
  						/* master 0 in error */
  #define FSI_MECTRL_P8_AUTO_TERM	0x4000		/* Auto terminate */
  
  #define FSI_HUB_LINK_OFFSET		0x80000
  #define FSI_HUB_LINK_SIZE		0x80000
  #define FSI_HUB_MASTER_MAX_LINKS	8
  
  /*
   * Protocol definitions
   *
   * These are used by low level masters that bit-bang out the protocol
   */

  /* Various protocol delays */
  #define	FSI_ECHO_DELAY_CLOCKS	16	/* Number clocks for echo delay */
  #define	FSI_SEND_DELAY_CLOCKS	16	/* Number clocks for send delay */
  #define	FSI_PRE_BREAK_CLOCKS	50	/* Number clocks to prep for break */
  #define	FSI_BREAK_CLOCKS	256	/* Number of clocks to issue break */
  #define	FSI_POST_BREAK_CLOCKS	16000	/* Number clocks to set up cfam */
  #define	FSI_INIT_CLOCKS		5000	/* Clock out any old data */
  #define	FSI_MASTER_DPOLL_CLOCKS	50      /* < 21 will cause slave to hang */
  #define	FSI_MASTER_EPOLL_CLOCKS	50      /* Number of clocks for E_POLL retry */
  
  /* Various retry maximums */
  #define FSI_CRC_ERR_RETRIES	10
  #define	FSI_MASTER_MAX_BUSY	200
  #define	FSI_MASTER_MTOE_COUNT	1000
  
  /* Command encodings */
  #define	FSI_CMD_DPOLL		0x2
  #define	FSI_CMD_EPOLL		0x3
  #define	FSI_CMD_TERM		0x3f
  #define FSI_CMD_ABS_AR		0x4
  #define FSI_CMD_REL_AR		0x5
  #define FSI_CMD_SAME_AR		0x3	/* but only a 2-bit opcode... */
  
  /* Slave responses */
  #define	FSI_RESP_ACK		0	/* Success */
  #define	FSI_RESP_BUSY		1	/* Slave busy */
  #define	FSI_RESP_ERRA		2	/* Any (misc) Error */
  #define	FSI_RESP_ERRC		3	/* Slave reports master CRC error */
  
  /* Misc */
  #define	FSI_CRC_SIZE		4
  
  /* fsi-master definition and flags */

  #define FSI_MASTER_FLAG_SWCLOCK		0x1

  /*
   * Structures and function prototypes
   *
   * These are common to all masters
   */

  struct fsi_master {
  	struct device	dev;
  	int		idx;
  	int		n_links;
  	int		flags;

  	struct mutex	scan_lock;

  	int		(*read)(struct fsi_master *, int link, uint8_t id,
  				uint32_t addr, void *val, size_t size);
  	int		(*write)(struct fsi_master *, int link, uint8_t id,
  				uint32_t addr, const void *val, size_t size);
  	int		(*term)(struct fsi_master *, int link, uint8_t id);
  	int		(*send_break)(struct fsi_master *, int link);

  	int		(*link_enable)(struct fsi_master *, int link,
  				       bool enable);

  	int		(*link_config)(struct fsi_master *, int link,
  				       u8 t_send_delay, u8 t_echo_delay);

  };
  
  #define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev)

  /**
   * fsi_master registration & lifetime: the fsi_master_register() and
   * fsi_master_unregister() functions will take ownership of the master, and
   * ->dev in particular. The registration path performs a get_device(), which
   * takes the first reference on the device. Similarly, the unregistration path
   * performs a put_device(), which may well drop the last reference.
   *
   * This means that master implementations *may* need to hold their own
   * reference (via get_device()) on master->dev. In particular, if the device's
   * ->release callback frees the fsi_master, then fsi_master_unregister will
   * invoke this free if no other reference is held.
   *
   * The same applies for the error path of fsi_master_register; if the call
   * fails, dev->release will have been invoked.
   */

  extern int fsi_master_register(struct fsi_master *master);
  extern void fsi_master_unregister(struct fsi_master *master);

  extern int fsi_master_rescan(struct fsi_master *master);

  #endif /* DRIVERS_FSI_MASTER_H */